To be honest, I don't see how this is a big concern. If you're getting statistics based on views, you may as well include your own views in the count - nobody else goes to the bother of removing them. If you're getting statistics based on visits (unique IPs or IP masks), then your visits won't make up a significant percentage of the total, and you may as well include them too.

Best thing to do is just cache the last x number of IPs in a text file and check the current IP against them. People who visit the site several times close together (like you) will only be counted once. If you want, you can also store timestamps, so people who visit your site again after x number of days will be counted even if they're still in the IP cache.